Download Record

Author

Date

Advisor

Second Reader

Metadata

Abstract

The objective of this study is to investigate the utility of acoustic tomography for performance assessment of a generic low frequency active sonar system. The performance of the sonar is simulated using tomography-derived sound speed data versus a range independent ocean model. The ocean environment used in the simulation is 159 tomographic snapshots of the Barents Sea Polar Front, taken every 5 minutes in August 1992. The modeled sonar system consists of a 1000 Hz source with a source level of 205.5 dB and a towed horizontal array of hydrophones. The system is derived from unclassified parameters of ATAS (Active Towed Array Sonar), built by Thomson Sintra ASM and British Aerospace SEMA, and the experimental ALF sonar, designed by FEL-TNO (the Netherlands) and built by Thomson Sintra ASM. The tomographic images over a range of 26 km provide a realistic ocean in which system performance is assessed. This study used a broadband, coupled normal mode, propagation model and assumed a noise-limited condition. The probability of detection calculated as a function of time for 13 hours is compared with that estimated using a range- and time-independent assumption. The utility of coastal acoustic tomography for tactical applications is discussed. (AN)

An acoustic tomography array consisting of six transceiver moorings was
jointly deployed by Woods Hole Oceanographic Institution and Scripps
Institution of Oceanography in the Greenland Sea during the second half of ...

A six transceiver ocean acoustic tomography array was deployed to monitor ocean ventilation and circulation over the 1988-89 winter cooling season. A stochastic inverse method computer code which attains a solution by ...

Ocean acoustic tomography is particularly suited to observing mesoscale
dynamic processes, which may not be adequately observed by more
conventional methods. Ships and buoys are limited in their sampling rates by
location ...